Artificial foot



J. F. ROWLEY ARTIFICIAL FOOT Filed Aug. 15, 1954 2 Sheets-Sheet l A N 9W J. F. ROWLEY ARTIFICIAL FOOT 2 Sheets-Sheet 2 Filed Aug. 13, 1934Patented Apr. 7, 1936 UNITED STATES PATENT OFFICE 7 Claims.

My invention relates to artificial feet and more particularly it relatesto improvements especially adapted for use with artificial feetcomprising an outer flexible foot form and a core of hard materialembedded therein.

It is an object of the invention to provide improved means operativelyconnecting the core with the flexible front or toe portion of the footin such a manner that the toe portion is thereby automaticallymaintained in natural position relative to the body of the foot andupward flexure and return movement of the toe portion is permitted inaccordance with the movement of the human foot while walking It isanother object of the invention to provide an artificial foot having aflexible front portion and means adapted to yieldingly hold the frontportion in its natural position and to permit it to be bent upwardlyunder the pressure exerted thereon in walking, the toe portion beingreturned to its natural position by the action of said means as soon asthe pressure is released Still another object of the invention is toprovide an artificial foot having a front or toe portion adapted to beflexed vertically in combination with means operable automatically forcontrolling the position of the toe relative to the body portion of thefoot in accordance with the nat ural movement of the foot in walking.

It is a further object of the invention to provide an artificial foothaving its component parts operatively connected in a manner such thatthe toe portion may be flexed by the normal pressure applied to the footin walking and be automatically returned to its normal position uponrelease of the applied pressure.

Many other objects and advantages of the construction herein shown anddescribed will be obvious to those skilled in the art from thedisclosures herein given. To this end my invention consists in the novelconstruction, arrangement and combination of parts herein shown anddescribed and more particularly pointed out in the claims.

In the drawings wherein like reference characters indicate like orcorresponding parts:

Fig. l is a longitudinal vertical sectional View of one form of a footembodying the principles of the invention;

Fig. 2 is a view along the line 22 of Fig. 1;

Fig. 3 is a perspective view of a rigid member operatively connectingthe main body and toe portions of the foot;

Fig. 4 is a longitudinal vertical sectional view of an artificial footshowing an alternative form of construction in which the principles ofthe invention are embodied;

Fig. 5 is a view along the line 5--5 of Fig. 4; and

Fig. 6 is a perspective view of a rigid member operatively connectingthe flexible toe portion of the foot with a rigid core positioned in themain body of the foot.

Referring now more particularly to the drawings, the numeral 10designates a core member of rigid material such as wood embedded in afoot form envelope ll preferably constructed of sponge rubber. A shinsection l2, including a transversely extending bottom member I 3, isconnected with the core member ID by means of a bearing hinge l4including a bolt l5 fastened to the shin section, a bolt l6 fastened tothe core member, and a pivot ll journalled in ball bearings. The shinmember I3 is spaced away from the core member II) to permit normalmovement of the foot relative to the shin member.

The core member I0 terminates slightly in ad- Vance of the ball of thefoot, the front or toe portion [8 of the envelope ll being free to beflexed upwardly about the ball of the foot except as restricted in amanner hereinafter more particularly described.

A spring rubber block I9, having its ends respectively mounted inapertures provided for that purpose in the rear portion of the shinmember 13 and the core member Ii], yieldingly holds the core and shinmembers in normal position. A spring rubber buffer 20, mounted in anaperture provided for that purpose in the forward end of the core member[0, is operatively connected with the flexible toe portion l8 of thefoot form by means of a rigid member 25. The mem-- ber 25 is shown inperspective in Fig. 3 as having a pair of spaced-apart prongs 24connected by a rod 21 and is shown in position in Fig. 1 with the prongsprojecting forwardly in the toe portion It.

The core member it is provided with a vertically extending opening 2|terminating in a forwardly extending longitudinal groove 22 in thebottom of the member. The member 25 is positioned in the groove 22 andhas its rear end projecting upwardly through the opening 21 with itsupper extremity turned forwardly to provide a flange 2t seated upon theblock 20. The member 25 is positioned with the rod 21 providing a pivotat the ball of the foot. The rod 21 is positioned in a groove 28,provided for that purpose in the bottom of the core member l0, and issurrounded by suitable lubricant material 29.

The mounting and construction of. the member 25 is such that the bufferblock 20 normally holds the rigid member 25 in the unfiexed position ofthe toe portion IS, the block yielding under pressure exerted thereon bythe rigid member as the toe portion of the foot is flexed upwardly inwalking. Upon release of the external pressure applied to the toeportion, the block 20 expands to its normal position thereby returningthe rigid member to its normal position and carrying along with it thetoe portion l8 to its original unflexed position.

The described arrangement and construction of the rigid member 25 issuch that the toe portion i8 may be flexed upwardly and be returned toits normal position in a manner corresponding to the natural movement ofthe human foot in walking and the foot is manipulated in the sameautomatic manner as the human foot.

An alternative embodiment of the invention is shown in Fig. 4 ascomprising a core member embedded in an envelope 3| of resilientmaterial such as sponge rubber or the like. A shin section 32 includinga transverse bottom member 33 is operatively connected with the coremember 33 by a ball bearing hinge 34 so arranged that the member 33 isnormally spaced apart from the core member. The hinge 34 is fastened tothe shin section by a bolt 35 and to the core member by a bolt 33, thebolts being connected in the usual manner by a pivot 31 journalled inball bearings.

The rear portions of the core member 35 and shin member 33 areyieldingly held in normal spaced-apart relation by a sponge rubber block33 having its opposite ends positioned in apertures respectivelyprovided in the members for that purpose. The front portions of themembers 35 and 33 are yieldingly held in normal spaced-apart relation bya buffer member 33 constructed of sponge rubber and surmounted by asolid bearing member 4| having its upper end positioned in a recess 54in the member 33.

A washer 42 separates the head of the member 4| from the buifer andserves to distribute the load coming from the shin member over the upperend of the buffer.

The core member 3|] terminates slightly in advance of the ball of thefoot and the front portion 38 of the foot, consisting entirely ofresilient material such as sponge rubber or the like, is adapted to beflexed about the ball of the foot as a pivot. In order that theresilient front portion 38 may function in walking in a manner similarto that of the human foot, I have provided a rigid member operativelyconnecting the front or toe portion 38 with the core member 3|). Therigid member 45 is shown in perspective in Fig. 6 as comprising a lever48 terminating in a pair of front prongs 46 which are embedded in thetoe portion 38 as shown in Fig. 4. The member 45 is provided with atransversely extending pivot member 41 rotatably mounted in a groove 52in the bottom of the member 30 adjacent the ball of the foot, the groovebeing filled with lubricant 53.

The core member 30 is provided with a vertically extending opening 43terminating in a forwardly extending longitudinal groove 44 in thebottom of the member. The lever portion 48 of the member 46 ispositioned in the groove 44 with its rear end providing a hook 49operatively engaged by the lower end of an extensile spring 5|positioned in the opening 43. The upper end of the spring 5| is fastenedto a supporting rod 50 so arranged that the rigid member 45 normallyoccupies a position corresponding to the unflexed position of the toeportion 38. Upward bending of the toe portion 33 by external pressure,such as that exerted in walking, rotates the rigid member 45 about thepivot 41 and extends the spring 5|. The spring 5| contracts and returnsthe member 45 and toe portion 38 to their normal positions upon therelease of such pressure. upwardly about the ball of the foot and isreturned to its normal position by the action of the member 45 uponrelease of pressure on the toe portion.

Thus it will be seen that I have provided novel improvements inartificial foot construction which are adapted to permit movement of thetoe portion relative to the main body of the foot in a mannercorresponding to the natural movement of the corresponding parts of thehuman foot in walking and which operates to automatically return the toeportion of the foot to its normal position when no external pressure isapplied thereto.

Having thus described my invention, it is obvious that variousimmaterial modifications may be made in the same without departing fromthe spirit of my invention; hence I do not wish to be understood aslimiting myself to the exact form, construction, arrangement andcombination of parts herein shown and described or uses mentioned.

What I claim as new and desire to secure by Letters Patent is:

1. In an artificial foot, a rigid core member, an envelope of resilientmaterial closely fitting the core member and providing a foot form, thecore member having its forward end terminating adjacent the ball portionof the foot and providing a vertical opening rearwardly of said ballportion, a rigid member carried by the core member and extendinglongitudinally along the bottom thereof, means providing a mounting forand adapting the rigid member to be tilted about a transverse horizontalaxis adjacent the ball of the foot, the front end of said rigid memberbeing embedded in the toe portion of the form and having its rearportion extending through said opening and projecting forwardly over thetop of the core member, a resilient member mounted on the top of thecore member and providing a cushion seat for the forwardly projectingportion of the rigid member, said cushion seat being adapted to normallymaintain the rigid member in a position corresponding to the unflexedposition of the toe portion and to yield under external pressure appliedto the bottom of the toe portion to permit upward movement thereof.

2. In an artificial limb, a rigid shin member, a rigid core member,means forming a rocker connection between said shin and core members, anenvelope of resilient material closely fitting the core member andproviding a foot form, the core member having its front portionterminating adjacent the ball portion of the foot, a rigid memberpivotally mounted intermediate its ends on the core member with onemovable end operatively related to the toe portion, and a resilientmember mounted on the core member in operative relation to the othermovable end of said rigid member in a manner to normally maintain saidrigid member in a position corresponding to the unflexed position of thetoe portion, said resilient member yieldable to permit movement of thetoe portion relative to the core member, said shin In walking the toeportion 38 is flexed member being operable by tilting movement to movesaid rigid member against the resistance of said resilient member.

3. In an artificial limb, a rigid core member, an envelope of resilientmaterial closely fitting the core member and providing a foot form, arigid shin member, means providing a rocker connection between said coreand shin members, the core member terminating adjacent the ball portionof the foot and providing an upwardly extending opening, a rigid memberembedded in said toe portion and extending through said opening with itsupper end projecting over the top of said core member, means providing amounting for and adapting the rigid member to be tilted about atransverse axis adjacent the ball of the foot, a resilient membermounted on the top of the core member in advance of said rockerconnection providing a cushion seat for said projecting end of the rigidmember, said cushion seat normally maintaining the rigid member in aposition corresponding to the natural relative positions of the toeportion, the shin member, and the core member, and resilient meansadapted to maintain the forward end of the shin member in engagementwith said projecting end of the rigid member, said cushion seat beingyieldable under pressure exerted thereon to permit relative tiltingmovement of the forward portions of the shin and core members the onetowards the other to actuate said rigid member to move the toe portionupwardly from its unflexed position.

4. In an artificial limb, a rigid core member, an envelope of resilientmaterial closly fitting the core member and providing a foot form, arigid shin member, means providing a rocker connection between said coreand shin members, the core member terminating adjacent the ball portionof the foot and providing an upwardly extending opening, a rigid memberembedded in said toe portion and extending through said opening with itsupper end projecting over the top of said core member, means providing amounting for and adapting the rigid member to be tilted about atransverse axis adjacent the ball of the foot, a resilient membermounted on the top of the core member in advance of said rockerconnection providing a cushion seat for said projecting end of the rigidmember, said cushion seat normally maintaining the rigid member in aposition corresponding to the natural relative positions of said toeportion, shin and core members, and resilient means adapted to maintainthe forward end of the shin member in engagement with said projectingend of the rigid member, said cushion seat being yieldable underpressure exerted thereon by actuation of the rigid member resulting fromforce applied to and resulting in movement of the toe portion upwardlyrelative to the core member.

5. In an artificial limb, a rigid core member, an envelope of resilientmaterial closely fitting the core member and providing a foot form, arigid shin member, means providing a rocker connection between said coreand shin members, the core member terminating adjacent the ball portionof the foot and providing an upwardly ex-' tending opening, a rigidmember embedded in said toe portion and extending through said openingwith its upper end projecting over the top of said core member, meansproviding a mounting for and adapting the rigid member to be tiltedabout a transverse axis adjacent the ball of the foot, a resilientmember mounted on the top of the core member in advance of said rockerconnection providing a cushion seat for said projecting end of the rigidmember, said cushion seat normally maintaining the rigid member in aposition corresponding to the respective relative natural positions ofthe toe portion, the shin member and the core member, and resilientmeans adapted to maintain the forward end of the shin member inengagement with said projecting end of the rigid member, said cushionseat being adapted to yield under pressure exerted thereon by said rigidmember resulting from relative movement of the shin and core members theone towards the other and to yield also under the pressure resultingfrom movement of the rigid member resulting from upward movement of thetoe portion by the application of external force to said toe portion. 6.In an artificial foot, a rigid core member having a vertical openingrearwardly of the ball I of the foot, resilient material providing afoot form enveloping said core member, a rigid member extendingforwardly from said opening along the bottom of the core member with itsfront end embedded in the toe portion of the form, means providing apivotal mounting for said rigid memher on said core member about atransverse axis adjacent the ball of the foot, the rear portion of saidrigid member extending through said opening with its end overlying thetop of the core member, and a cushion member providing a seat for saidoverlying end of the rigid member.

7. In an artificial foot, a rigid core member having a vertical openingrearwardly of the ball of the foot, resilient material providing a footform enveloping said core member, a rigid mem ber extending forwardlyfrom said opening along the bottom of the core member with its front endproviding a fork embedded in the toe portion of the form, meansproviding a pivotal mounting for said rigid member on said core memberabout a transverse axis adjacent the ball of the foot, the rear portionof said rigid member extending through said opening with its endoverlying the top of the core member, and a cushion member providing aseat for said overlying end of the rigid member. said cushion membernormally maintaining the rigid member in a position corresponding to theunflexed position of the toe portion of the said form and yieldable topermit upward bending of said toe portion.

JAMES F. ROWLEY.

